Composition and use thereof for ink jet printing

ABSTRACT

A composition comprising: 
     (a) a cationic substance; 
     (b) an acid generator; and 
     (c) an alkyl or a hydroxyalkyl substituted starch. 
     Also claimed is a polyamide textile material treated with the composition, a method for ink jet printing onto a polyamide textile material which has been treated with the composition and a polyamide material printed using the method.

The present invention relates to a composition suitable for applicationto polyamide textile materials, to a polyamide textile material treatedwith the composition, to an ink jet printing method, and to a polyamidetextile material coloured using the method.

The printing of textiles is conventionally carried out by screen orroller printing using gravure engraved cylinders. The design to beprinted has to be engraved on to a cylinder and each individual colourin a design requires the application of a separate screen with a colourpre-mixed to the required shade. This is a long and slow process and itcan take many months for a textile design to appear as a printedtextile. Consequently, there is a demand for a printing process whichenables new designs to be printed onto a textile quickly for proofingpurposes and for small production runs. Ink jet printing of textilesoffers the potential to transfer a design to a textile much faster thantraditional textile printing methods.

The prints prepared using ink jet printing are required to meet manydemanding criteria, for example the prints are preferably bright, have ahigh water-fastness and good light-fastness. In addition, the ink jetprinting process is preferably capable of producing prints which exhibita colour gamut comparable to that obtained using conventional printingmethods.

PCT application no. GB97/03423 discloses a method of ink jet printingwherein the colour gamut achievable using ink jet printing onto, interalia, cellulosic textiles is increased by using up to eight reactivedyes.

U.S. Pat. No. 5,645,631 discloses a ink jet printing using inkscontaining a reactive dye onto a cellulosic material which has aspecific fibre length and moisture regain.

U.S. Pat. No. 5,698,478 discloses ink jet printing using inks containinga reactive dye onto a cellulosic textile material containing 0.1 to 50%by weight of a cationic substance, 0.01 to 5% by weight of an alkalinesubstance and 0.01 to 20% by weight of the ammonium salt of a polyvalentacid.

The above ink jet printing methods fix the dyes by means of a covalentbond formed between cellulosic textiles and reactive group(s) present inthe dyes by heating the printed textile under alkaline conditions.

We have found that when reactive dyes are applied to polyamide textiles,especially silk, using ink jet printing followed by fixing the dyes byheating under alkaline conditions, the resulting prints are often dulland exhibit a poor colour gamut compared to prints obtained usingconventional printing techniques.

U.S. Pat. No. 5,594,485 discloses ink jet printing of acid dyes ontosilk wherein the silk has a specified moisture content. However, thecolour gamut available through ink jet printing of acid dyes is verylimited compared to that obtained using conventional printing methods.

There is, therefore, a need for an ink jet printing method whichprovides prints on polyamide textiles which exhibit a brightness andcolour gamut comparable to that obtained by printing such materialsusing conventional printing techniques.

We have found that the brightness and colour gamut of prints obtained byink jet printing with inks containing various classes of anionic dyesonto a polyamide textile material is improved by applying apre-treatment composition to the polyamide material.

According to a first aspect of the present invention there is provided afirst composition comprising:

(a) a cationic substance;

(b) an acid generator; and

(c) an alkyl or a hydroxyalkyl substituted starch.

Preferably the composition is free from alkaline materials.

Preferably the composition comprises:

from 0.5 to 99.5, more preferably from 5 to 80 and especially from 10 to80 parts of component (a);

from 0.1 to 60, more preferably from 0.5 to 50 and especially from 2 to45 parts of component (b);

from 0.1 to 99.5, more preferably from 0.5 to 80 and especially from 8to 70 parts of component (c);

wherein all parts are by weight and the sum of the parts of components(a)+(b)+(c)=100.

The cationic substance is preferably a cationic polymer or a quaternaryammonium compound.

Preferred cationic polymers are polymers which carry a quaternaryammonium group. The cationic polymer is preferably a copolymer formed bypolymerising a monomer containing a quaternary ammonium salt, with oneor more monomers selected from vinyl pyrrolidone, acrylamide, allylamineand ethyleneimine.

Especially preferred cationic polymers are:

(a) cationic polyethylenimines;

(b) cationic polymers as described in U.S. Pat. No. 5,698,478, cols. 4to 6, the contents of which are incorporated herein by referencethereto; and

(c) dicyanamide/phenol—formaldehyde/ammonium chloride condensate, forexample the 50% aqueous solution available as MATEXIL™ FC-PN from ICILimited.

Preferred quaternary ammonium compounds are of the Formula (1):

wherein:

R¹, R² and R³ are each independently selected from H, optionallysubstituted C₁₋₂₀-alkyl and optionally substituted C₂₋₂₀-alkenyl; R⁴ isoptionally substituted C₁₋₂₀-alkyl or optionally substitutedC₂₋₂₀-alkenyl; and X⁻ is an anion.

Preferably R¹ and R² are each independently selected from C₁₋₂₀-alkyl orC₂₋₂₀-alkenyl, more preferably C₁₋₄-alkyl, especially methyl.

R³ and R⁴ are preferably each independently C₅₋₂₀-alkyl orC₅₋₂₀-alkenyl, especially C₁₆₋₂₀-alkyl or C₁₆₋₂₀-alkenyl and moreespecially C₁₈-alkyl.

When any of the groups R¹, R², R³ or R⁴ is alkyl or alkenyl it may bebranched or, preferably, straight chain.

Preferred alkyl groups represented by R¹, R², R³ and R⁴ are of formula—(CH₂)_(n)CH₃ wherein n has a value of from 0 to 19.

It is preferred that R³ and R⁴ are each independently of Formula—(CH₂)_(n)CH₃ wherein n is from 9 to 19, especially 15 to 19, moreespecially 17.

Preferably R¹ and R² are identical. In one preferred embodiment R², R³and R⁴ are identical.

The nature of the anion represented by X⁻ is not believed to becritical. However, preferred anions include ½ (SO₄ ²⁻) and halide, andespecially Cl⁻.

The compounds of Formula (1) preferably contain 30 or more, morepreferably 30 to 50, especially 32 to 48 and more especially 36 to 40carbon atoms.

Preferred compounds of Formula (1) include tetraoctylammonium salts,tridecyl ammonium salts, tridodecylammonium salts, tetradecylammoniumsalts, tridecylmethyl ammonium salts, tridodecylmethylammonium salts,distearyldiethylammonium salts, distearyldipropylammonium salts, morepreferably distearyldimethylammonium salts, and especially the precedingquaternary ammonium compounds with a chloride, sulphate or bromideanion. An especially preferred compound of Formula (1) is distearyldimethylammonium chloride.

Component (a) of the composition is preferably a quaternary ammoniumcompound because we have found that the presence of such a compound inthe composition gives prints which exhibit a very high colour yield.

The acid generator (component (b)) is preferably an organic or inorganicacid, and more preferably an organic acid, or a salt thereof. Theorganic acid may be monobasic or polybasic. It is especially preferredthat the acid generator is an organic polybasic acid, or a salt thereof.

Preferred organic monobasic acids comprise an aromatic or aliphaticgroup substituted with a group selected from —COOH, —PO₃H₂ and —SO₃H,especially —COOH. Preferred aliphatic monobasic acids comprise anoptionally substituted alkyl group which carries an acid group,preferably a —COOH group. The alkyl group is preferably C₁₋₁₂-alkyl, andmore preferably C₁₋₆-alkyl. When the aliphatic monobasic acid issubstituted the substituent(s) is/are preferably selected from —OH and—NH₂. Examples of preferred aliphatic monobasic acids include aceticacid, propionic acid, butyric acid, isobutyric acid, pentanoic acid,2,2-dimethylpropanoic acid, glycolic acid, lactic acid and glycericacid.

Preferred aromatic monobasic acids comprise an aromatic groupsubstituted with —COOH, —SO₃H or —PO₃H₂, more preferably —COOH.Preferred aromatic groups are phenyl, naphthyl, pyridinyl, furanyl,thiofuranyl or benzyl each of which is optionally substituted. Morepreferably the aromatic group is optionally substituted phenyl oroptionally substituted pyridinyl.

Preferred examples of monobasic aromatic acids include nicotinic acid,isonicotinic acid, salicylic acid, anisic acid, vanillic acid and gallicacid.

Preferred organic polybasic acids include aromatic polybasic acids andaliphatic polybasic acids.

Preferred aromatic polybasic acids are optionally substituted benzene,pyridine or naphthylene groups which carry two or more groups selectedfrom —SO₃H, —COOH and —PO₃H₂. It is especially preferred that thearomatic polybasic acid carries 2 or 3 acid groups selected from —SO₃Hand —COOH.

The optional substituents which may be present on the aromatic groups ofaromatic monobasic acids and aromatic polybasic acids are preferablyselected from halogen (especially F or Cl); —NO₂; —CF₃; —CN; aC₁₋₆-alkyl, C₂₋₆-alkenyl, C₅₋₈-cycloalkyl or C₁₋₆-alkoxy groupoptionally substituted by —OH, —NH₂, —NO₂ or halogen; a group of theformula —SR⁵, or —COOR⁵ wherein R⁵ is H, C₁₋₄-alkyl, C₅₋₈-cycloalkyl orphenyl; and groups of the formula —OR⁶, —COR⁶; —NR⁶R⁷, —SO₂NR⁶R⁷, —SOR⁶,—SO₂R⁶, —NR ⁶COR⁷, —CONR⁶R⁷, or —OCOR⁶, wherein R⁶ and R⁷ eachindependently represent H, C₁₋₄alkyl, C₅₋₈-cycloalkyl, phenyl or R⁶ andR⁷ together with the nitrogen to which they are attached form a 5 or 6membered ring, for example piperazine or morpholine.

Especially preferred aromatic polybasic acids include for examplephthalic acid, isophthalic acid and terephthalic acid.

Preferred aliphatic polybasic acids contain up to 20 carbon atoms. Thealiphatic polybasic acids preferably comprise an aliphatic group whichcarries 2 to 8, more preferably 2 to 6, especially 2 or 3 and moreespecially 2, groups selected from —SO₃H, —COOH and —PO₃H₂. Thealiphatic polybasic acid may be saturated or unsaturated.

Preferred acid groups in the aliphatic polybasic acids are selected from—COOH and —SO₃H, and especially —COOH.

Preferred saturated aliphatic groups are alkanes and preferredunsaturated groups are alkenes and alkynes. The alkane, alkene andalkyne groups may be straight chain, branched chain or cyclic and areoptionally interrupted by one or more groups or heteroatoms, for example—O—, —S—, —NR⁸—, optionally substituted phenylene, piperazinylene and—C(O)—, wherein R¹ is H, optionally substituted alkyl, or optionallysubstituted phenyl.

The alkane and alkene groups optionally contain further substituents,preferably selected from —SH, or —OR⁶, wherein R⁶ is as hereinbeforedefined, more preferably —OH.

When the alkane, alkene or alkyne group is interrupted by an optionallysubstituted phenylene group, it is preferred that the optionalsubstituents on the phenylene are selected from —OH, —NO₂, —NH₂,C₁₋₄-alkyl, —SH, —COOH and —SO₃H.

Preferably R⁸ is H, C₁₋₄-alkyl, C₁₋₄-alkyl substituted by —OH, phenyl orphenyl substituted by —OH, —NH₂, —NO₂, C₁₋₄-alkyl or C₁₋₄-alkylsubstituted by —OH.

Especially preferred aliphatic polybasic acids are dicarboxylic acids ofthe Formula (2):

HOOC—W—COOH  (2)

wherein:

W is an optionally substituted, optionally interrupted alkylene,alkenylene or alkynylene group.

When W is a substituted alkenylene group, it is preferably substitutedby —OH.

Preferred groups which may interrupt W are —O—, —S—, —NH—, —C(O)—andphenylene optionally substituted by —OH, —NH₂, —SH, —COOH or —SO₃H.

Examples of optionally substituted alkenylene and alkynylene groupsinclude —CH═CH—,—CH₂CH═CH—, —CH₂CH═CHCH₂—, —C═C—and —CH₂C═—CCH₂—.

Preferred interrupted alkylene groups are of the formula:

—C₂H_(2a)—L—C_(b)H_(2b)—

wherein:

L is —O—, —S—, —NH—, —C(O)—or phenylene optionally substituted by —OH,—NH₂, —SH, —COOH or —SO₃H;

a is an integer from 1 to 17; and

b is an integer from 1 to 17, provided that (a+b)≦18.

Examples of preferred groups represented by L include —CH₂—O—CH₂—,—CH₂—C₆H₄—CH₂—, —CH₂C₆H₄CH₂—, —CH₂C(O)CH₂—, and —CH₂SCH₂—.

Preferably W is an optionally substituted straight or branched chainalkylene group. When W is a substituted alkylene group it is preferablysubstituted by one or more —OH groups. Examples of such groups include—CH(OH)—, —CH(OH)CH(OH)—and —CH₂CH(OH)—.

It is especially preferred that W is a group of the formula—C_(m)H_(2m)—, wherein m is 1 to 18, preferably 1 to 10 and especially 1to 8.

Preferred dicarboxylic acids of the Formula (2) when W is an alkenylenegroup include for example, maleic acid, fumaric acid, citraconic acidand itaconic acid.

Preferred dicarboxylic acids of the Formula (2) when W is alkylenesubstituted by —OH include for example, malic acid, tartronic acid,tartaric acid and mucic acid.

Preferred dicarboxylic acids of the Formula (2) when W is group of theformula —C_(m)H_(2m)—, wherein m is as hereinbefore defined include, forexample, malonic acid, succinic acid, glutaric acid, adipic acid,pimelic acid, suberic acid, azelaic acid and sebacic acid anddodecanedioc acid.

Preferred dicarboxylic acids of the Formula (2) when W is a cyclicalkylene or alkenylene group include, for example, cyclohexenedicarboxylic acid and cyclohexane dicarboxylic acid.

Further examples of aliphatic polybasic acids suitable for use in thepresent invention include, but are not limited to, tribasic acids,especially citric acid, and dibasic acids, for example oxalic acid.

When the acid generator is present as a salt preferred salts includesodium, lithium and ammonium salts and salts with volatile amines. It ispreferred, however, that the acid generator is in free acid form.Preferably the acid generator is colourless.

Preferred acid generators are selected from nicotinic acid, citric acid,tartaric acid and malonic acid, more especially citric acid andnicotinic acid.

When component (c) is an alkyl-substituted starch, the starch ispreferably substituted by C₁₋₆-alkyl, more preferably C₁₋₄-alkyl.

When component (c) is hydroxyalkyl substituted starch the starch ispreferably substituted by C₂₋₄-hydroxyalkyl, more preferably byhydroxyethyl or hydroxypropyl groups.

Preferably the starch is corn starch, wheat starch, rice starch, potatostarch or tapioca starch, more preferably potato starch or tapiocastarch. The starch is preferably substituted at the free hydroxyl groupsof the D-glucopyranose rings of the starch. The degree of substitutionon the starch is 0.05 to 3, more preferably 0.05 to 2 and especially0.05 to 0.5 per D-glucopyranose ring.

An especially preferred component (c) is hydroxypropyl or hydroxyethylsubstituted tapioca starch. More especially component (c) ishydroxypropyl substituted tapioca starch, for example Solvitose WBavailable from Avebe, Holland.

The starch may by substituted using known methods. For example it may behydroxyethylated or hydroxypropylated by heating a slurry of granularstarch in an lower aliphatic alcohol (preferably a C₁₋₃-alchohol) with aGroup I or II metal hydroxide (preferably NaOH) in the presence of asmall amount of water (up to 10% by weight) and reacting the alkalineslurry with ethylene oxide or propylene oxide at a temperature of 40 to120° C.

The starch may be alkylated by heating an alkaline aqueous suspension ofstarch with an appropriate alkylchloride. The reaction is preferablyperformed in the presence of an alkali metal chloride such as NaCl.

It is preferred that the composition according to the first aspect ofthe invention is used in a liquid medium because this helps to achieve auniform coating and good impregnation when the composition is applied toa polyamide textile material.

According to a second aspect of the present invention there is provideda composition comprising the composition according to the first aspectof the present invention and a liquid medium.

Preferably the liquid medium is an aqueous medium, more preferably wateror a mixture of water and one or more water-soluble organic solvent(s).

In view of the foregoing preferences an especially preferred compositionaccording to the second aspect of the present invention comprises:

(a) from 0.1 to 20, more preferably from 0.5 to 5 parts of a quaternaryammonium compound;

(b) from 0.05 to 40, more preferably from 0.1 to 30 parts of an organicacid (preferably an organic polybasic acid), or a salt thereof;

(c) from 0.05 to 30, more preferably 0.1 to 10 parts of an alkyl orhydroxyalkyl substituted starch; and

(d) from 30 to 95, more preferably 40 to 90 parts of an aqueous medium;

wherein all parts are by weight and the sum of the parts of component(a)+(b)+(c)+(d)=100.

Preferably the pH of the second composition is in the range of from 2 to7, more preferably from 3 to 6 and especially from 3.5 to 5.5.

The viscosity of the second composition at 25° C is preferably from 15to 60, more preferably from 15 to 50, especially from 25 to 45 and moreespecially from 40 to 50 cP.

The first composition is preferably dispersed or dissolved in the liquidmedium to give the second composition.

According to a third aspect of the present invention there is provided apolyamide textile material treated with a composition according to thefirst or second aspect of the present invention.

Preferably the polyamide textile material is a natural or syntheticpolyamide textile material, a blend of natural and synthetic polyamidetextile materials or a blend of a polyamide with one or more othersynthetic textile materials which is not a polyamide textile material,for example a polyester (for example Lycra™ available from Dupont).Preferred natural polyamide textile materials include for example, wool,silk, hair and hair based textiles such as cashmir. Preferred syntheticpolyamide textile materials include Nylon 6, Nylon 6,6 and Nylon 11. Itis especially preferred that the polyamide textile material is silk.

Preferred compositions used to treat the polyamide textile material areas defined in the first and second aspects of the present invention. Itis preferred however, that the polyamide material is treated with acomposition according to the second aspect of the present invention.

The polyamide textile material may be treated with the compositionaccording to the second aspect of the invention using any convenientmethod, for example by dip coating, roller coating, K-bar coating,printing, ink jet printing or by padding the surface of the materialwith the composition. It is especially preferred that the material istreated by padding the composition onto the material.

According to a fourth aspect of the present invention there is provideda method for the coloration of a polyamide textile material comprisingthe steps:

i) treating the polyamide textile material with a composition accordingto the second aspect of the present invention;

ii) applying by means of an ink jet printer an ink compositioncomprising a liquid medium and a water-soluble anionic dye, or a saltthereof, to the product of step i); and

iii) heating the product of step ii) at a temperature of from 50° C to250° C.

The product of step i) is conveniently a treated polyamide textilematerial according to the second aspect of the present invention. It isespecially preferred that the polyamide material is silk.

The composition applied to the material in step i) is preferably anaqueous composition as hereinbefore defined in the second aspect of thepresent invention.

The material in stage i) is preferably treated by padding thecomposition defined in the second aspect of the invention onto thematerial.

Preferably the product of step i) is dried before step ii) is performed.Drying may be performed using any convenient method, for example bysqueezing the material between rollers or by heating the material, forexample by exposure to hot air or direct heating, for example byinfra-red radiation, or micro-wave radiation, preferably so that thetemperature of the material does not exceed 100° C.

Preferably the ink composition used in step ii) of the present methodcomprises a water-soluble anionic dye and a liquid medium.

Preferred water-soluble anionic dyes are water-soluble anionic direct,reactive and acid dyes, for example azo, bis azo, tris azo andphthalocyanine dyes which preferably contain one, or more preferably twoor more, groups selected from —COOH, —SO₃H and PO₃H₂ in the free acid orsalt form.

Preferred direct dyes include for example Cl Direct Black 9, 17, 19, 22,32, 51, 56, 62, 69, 77, 80, 91 94, 97, 108, 112, 113, 114, 117, 118,121, 122, 125, 132, 146, 154, 166, 168, 173, 195 and 199; Cl Direct Blue1, 10, 15, 22, 25, 55, 67 ,68, 71, 76, 77, 78, 80, 84, 86, 87, 90, 98,106, 108, 109, 151, 156, 158, 159, 160, 168, 189, 192, 193, 194, 199,200, 201, 202, 203, 207, 211, 213, 214, 218, 225, 229, 236, 237, 244,248, 249, 251, 252, 264, 270, 280, 288, 289, 291 and 307; Cl DirectGreen 26, 27, 28, 29, 30, 31, 33, 34, 59, 63, 65, 66, 67, 68, 74, 80,85, 89; Cl Direct Yellow 8, 9, 11, 12, 27, 28, 29, 33, 35, 39, 41, 44,50, 53, 58, 59, 68, 86, 87, 93, 95, 96, 98, 100, 106, 108, 109, 110,130, 132, 142, and 173; Cl Direct Violet 106 and 107; Cl Direct Orange6, 15, 18, 26 29, 34, 37, 39, 40, 41, 46, 49, 51, 57, 62, 71, 105, 107and 115; Cl Direct Red 2, 4, 9, 23, 26, 31 39, 62, 63, 72, 75, 76, 79,80, 81, 83, 84, 89, 92, 95, 111, 173, 184, 207, 211, 212, 214, 218, 221,223, 224, 225, 226, 227, 232, 233, 240, 241, 242, 243 and 247.

Preferred acid dyes include, Cl Acid Yellow 17, 19, 23, 25, 39, 40, 42,44, 49, 50, 61, 64, 76, 79, 110, 127, 135, 143, 151, 159, 169, 174, 190,195, 196, 197, 199, 218, 219, 222, 227; Cl Acid Orange 3, 19, 24, 28:1,33, 43, 45, 47, 51, 67, 94, 116, 127, 138, 145, 156; Cl Acid Red 35, 42,52, 57, 62, 80, 82, 111, 114, 118, 119, 127, 128, 131, 143, 151, 154,158, 249, 257, 261, 263, 266, 299, 301, 336, 337, 361, 396, 397; Cl AcidViolet 5, 34, 43, 47, 48, 90, 103, 126; Cl Acid Blue 9, 25, 40, 41, 62,72, 76, 78, 80, 82, 90, 106, 112, 112, 113, 120, 127:1, 129, 138, 143,158, 175, 181, 205, 207, 220, 221, 230, 232, 247, 258, 260, 264, 271,277, 278, 278, 279, 280, 288, 290, 326; Acid Green 16, 17, 19, 20, 25,28, 40, 41, 71; Cl Acid Black 7, 24, 29, 48, 52:1.

Preferred reactive dyes include Cl Reactive Yellow 2, 3, 3:1, 13, 14,15, 17, 18, 23, 24, 25, 26, 27, 29, 35, 37, 41, 42, 49, 50, 52, 54, 55,57, 58, 63, 64, 75, 76, 77, 79, 81, 82, 83, 84, 85, 87, 88, 91, 92, 93,95, 96, 111, 115, 116, 131, 135; Cl Reactive Orange 5, 7, 10, 11, 12,13, 15, 16, 20, 30, 34, 35, 41, 42, 44, 45, 46, 56, 57, 62, 63, 64, 67,69, 71, 72, 73, 74, 78, 82, 84, 87; Cl Reactive Red 3, 3;1, 13, 17, 19,21, 22, 23, 24, 29, 31, 35, 37, 40, 41, 43, 45, 49, 55, 56, 58, 63, 67,80, 81, 82, 85, 86, 87, 104, 106, 108, 109, 110, 111, 112, 113, 114,117, 118, 119, 120, 123, 124, 126, 128, 130, 131, 132, 141, 147, 158,159, 170, 171, 174, 176; Cl Reactive Blue 2, 3, 5, 8, 10, 13, 14, 15,17, 18, 19, 21, 25, 26, 27, 28, 29, 38, 39, 40, 42, 43, 49, 51, 52, 65,66, 67, 68, 71, 73, 74, 75, 77, 78, 79, 80, 89, 98, 100, 101, 104, 105,112, 113, 114, 116, 119, 147, 148, 158, 160, 162, 169, 170, 171, 179,182, 187; Cl Reactive Green 5, 8, 12, 14, 15, 16, 19, 21; Cl ReactiveBlack 4, 5, 8, 14, 21, 23, 26, 31, 32, 34.

Further preferred anionic dyes include Projet Fast Black 2, Pro-JetBlack 1, Pro-Jet Fast Cyan 2, Pro-Jet Cyan 1, Pro-Jet Magenta 1, Pro-JetMagenta 1T, Pro-Jet Fast Magenta 2, Pro-Jet, Projet Magenta 3B-OA,Pro-Jet Yellow 1, Pro-Jet Yellow 1 G, Pro-Jet Yellow OAM, Pro-Jet RedOAM, Pro-Jet Blue OAM (all of which are available from ZenecaSpecialties or its successor) and the dyes disclosed in PCT applicationnumber GB97/03423 which are incorporated herein by reference thereto.

The present method enables a wide range of water-soluble anionic dyes tobe printed onto a polyamide textile material. Accordingly thewater-soluble anionic dyes in the inks used in step ii) can be selectedsuch that the colour gamut of the resulting print is maximised, whilstmaintaining a high colour yield and good dye fixation of on thesubstrate.

A preferred set of inks for use in step ii) of the present methodcomprises one or more inks selected from:

(a) a black ink comprising a liquid medium and a dye selected from ClDirect Black 195, Cl Direct Black 168 and Cl Direct Black 19;

(b) a cyan ink comprising a liquid medium and a dye selected from ClAcid Blue 9, Cl Acid Bluel58, Cl Acid blue 90 and Direct Blue 199;

(c) a magenta ink comprising a liquid medium and a dye selected from ClAcid Red 52, Cl Acid Red 249, Cl Direct Violet 107, Cl Direct Violet 106and Cl Reactive Red 31;

(d) a yellow ink comprising a liquid medium and a dye selected from ClDirect Yellow 86, Direct Yellow 132, Direct Yellow 173 Cl ReactiveYellow 85 and Cl Acid Yellow 23; and optionally

(e) one or more inks comprising a liquid medium and a dye selected fromthe dyes of the Formula (1) to (13) described in PCT application numberGB97/03423 which is incorporated herein by reference thereto.

Preferably the ink contains from 0.05 to 25 parts, more preferably 0.5to 20 and especially 2 to 15 parts by weight of the water-solubleanionic dye.

Preferred liquid media include water, a mixture of water and an organicsolvent and an organic solvent free from water.

When the medium comprises a mixture of water and an organic solvent, theweight ratio of water to organic solvent is preferably from 99:1 to1:99, more preferably from 99:1 to 50:50 and especially from 95:5 to80:20.

It is preferred that the organic solvent present in the mixture of waterand organic solvent is a water-miscible organic solvent or a mixture ofsuch solvents. Preferred water-miscible organic solvents includeC₁₋₆alkanols, preferably methanol, ethanol, n-propanol, isopropanol,n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol andcyclohexanol; linear amides, preferably diriethylformamide ordimethylacetamide; ketones and ketone-alcohols, preferably acetone,methyl ether ketone, cyclohexanone and diacetone alcohol; water-miscibleethers, preferably tetrahydrofuran and dioxane; diols, preferably diolshaving from 2 to 12 carbon atoms, for example pentane-1,5-diol, ethyleneglycol, propylene glycol, butylene glycol, pentylene glycol, hexyleneglycol and thiodiglycol and oligo- and poly-alkyleneglycols, preferablydiethylene glycol, triethylene glycol, polyethylene glycol andpolypropylene glycol, preferably polyethylene glycol with an averagemolecular weight of 200, 300 or 400; triols, preferably glycerol and1,2,6-hexanetriol; mono-C₁₋₄-alkyl ethers of diols, preferablymono-C₁₋₄-alkyl ethers of diols having 2 to 12 carbon atoms, especially2-methoxyethanol, 2-(2-methoxyethoxy)ethanol,2-(2-ethoxyethoxy)-ethanol, 2-[2-(2-methoxyethoxy)ethoxy]ethanol,2-[2-(2-ethoxyethoxy)-ethoxy]-thanol and ethyleneglycol monoallylether;polyalkoxylated naphthols, preferably those described in EP 555 950which are incorporated herein by reference thereto, more preferablypolyalkoxylated 2-naphthols and especially polyethoxylated 2-naphthols;cyclic amines, preferably optionally substituted morpholine; cyclicamides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone,N-ethyl-2-pyrrolidone, caprolactam and 1,3-dimethylimidazolidone; cyclicesters, preferably caprolactone; sulphoxides, preferably dimethylsulphoxide and sulpholane. Preferably the liquid medium comprises waterand 2 or more, especially from 2 to 8, water-soluble organic solvents.

Especially preferred water-soluble organic solvents are cyclic amides,especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone;diols, especially 1,5-pentane diol, ethyleneglycol, thiodiglycol,diethyleneglycol and triethyleneglycol; triols, especially glycerol;polyethylene glycols, especially polyethylene glycol 200 andpolyethylene glycol 400; mono-C₁₋₄-alkyl and C₁₋₄-alkyl ethers of diols,more preferably mono-C₁₋₄-alkyl ethers of diols having 2 to 12 carbonatoms, especially 2-methoxy-2-ethoxy-2-ethoxyethanol; polyethoxylated2-naphthol; and compounds of the Formula (3):

wherein:

R⁹ and each R¹⁰ independently is H or optionally substituted alkyl; and

t has a value of 1 to 4.

Preferably R⁹ and each R¹⁰ independently is H or C₁₋₅-alkyl optionallysubstituted by —OH, —NH₂, —SO₃H or —COOH, more preferably H orC₁₋₄-alkyl optionally substituted by —OH. It is especially preferredthat R¹⁰ is H and R⁹ is H or C₂₋₄-hydroxy alkyl.

Preferred compounds of Formula (3) include, for example morpholine,4-(2-hydroxyethyl)morpholine, 4-(3-hydroxypropyl)morpholine and4-methylmorpholine.

Examples of further suitable ink media comprising a mixture of water andone or more organic solvents are described in U.S. Pat. No. 4,963,189,U.S. Pat. No. 4,703,113, U.S. Pat. No. 4,626,284 and EP, 4,251,50A.

When the liquid medium comprises an organic solvent substantially freefrom water, (i.e. less than 1% water by weight) the solvent preferablyhas a boiling point of from 30° to 200° C., more preferably of from 400to 150° C., especially from 50 to 125° C. The organic solvent may be awater-immiscible solvent, a water-miscible solvent or a mixture of suchsolvents. Preferred water-miscible organic solvents are any of thehereinbefore described water-miscible organic solvents and mixturesthereof. Preferred water-immiscible solvents include, for example,aliphatic hydrocarbons; esters, preferably ethyl acetate; chlorinatedhydrocarbons, preferably CH₂Cl₂; and ethers, preferably diethyl ether;and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent,preferably a polar solvent is included because this enhances solubilityof the dye in the liquid medium. Examples of polar solvents includeC₁₋₄-alcohols. In view of the foregoing preferences it is especiallypreferred that where the liquid medium is an organic solvent free fromwater it comprises a ketone (especially methyl ethyl ketone) and/or analcohol (especially a C₁₋₄-alkanol, more especially ethanol orpropanol).

When the liquid medium is an organic solvent substantially free fromwater it is preferably a mixture of 2 to 5 different organic solvents.This allows a medium to be selected which gives good control over thedrying characteristics and storage stability of the ink.

The ink may also contain additional components conventionally used inink jet printing inks, for example viscosity and surface tensionmodifiers, corrosion inhibitors, biocides, kogation reducing additivesand surfactants which may be ionic or non-ionic.

In a first preferred embodiment of the present method the inks used instage ii) comprise:

(a) from 0.05 to 30, more preferably from 1 to 15 parts of awater-soluble anionic dye;

(b) from 0.01 to 50, more preferably from 1 to 30 and especially 2 to 10parts of a compound of the hereinbefore defined Formula (3);

(c) from 0 to 50, more preferably from 0.5 to 25 and especially from 2to 10 parts of 2-pyrrolidone;

(d) from 0 to 30, more preferably 0 to 20 and especially 2 to 10 partsof one or more compounds selected from glycerol, polyethylene glycol200, polyethylene glycol 400 or a polyethoxylated 2-naphthol;

(e) from 40 to 99, more preferably from 50 to 95, and especially from 55to 85 parts water;

wherein all parts are by weight and the sum of the parts(a)+(b)+(c)+(d)+(e)=100.

The inks according to this first preferred embodiment exhibit excellentjetting performance when incorporated into an ink jet printer. The inksare very stable, exhibit minimal crusting and provide high qualityprints when used in the present method.

Preferably component (a) of the preferred inks is selected from, Cl AcidYellow 23, Cl Direct Blue 199, Cl Acid Red 52, CI Acid Blue 158, Cl AcidBlue 9, Cl Direct Black 168 and Cl Reactive Yellow 85 all of which arecommercially available from Zeneca Limited.

Preferably component (b) of the preferred inks is morpholine or 4-(2-5hydroxyethyi)morpholine.

Preferably component (d) of the preferred inks is glycerol.

The inks according to this preferred embodiment are suitable forprinting (especially by means of an ink jet printer) onto a wide rangeof substrates in addition to polyamide textile materials. Suitableadditional substrates include cellulosic textile materials, paper,plastic (especially over head projector slides), metal and glass.Especially preferred substrates are polyamide textile materials,cellulosic textile materials (especially cotton), plain paper andtreated papers which may have an acid, alkaline or neutralcharacteristic.

Any ink jet printer may be used in stage ii) of the method according tothe fourth aspect of the invention. Preferred ink jet printers are dropon demand (DOD) and continuous printers. In DOD ink jet printingdiscrete droplets of ink are ejected from a reservoir through a smallorifice in response to an electrical recording signal so that thedroplets of ink are directed at a substrate. Preferred DOD ink jetprinters are piezoelectric ink jetprinting and thermal ink jet printing.In thermal ink jetprinters, programmed pulses of heat are applied to theink in the reservoir by means of a resistor adjacent to the orifice,during relative movement between the substrate and the reservoir. Inpiezoelectric ink jet printers the ink is ejected from the orificethrough the expansion and contraction of an ink reservoir formed from apiezoelectric material.

In continuous ink jet printers a stream of ink droplets are ejected froma small orifice and electrical fields are used to either direct thedroplets towards a substrate or into a gutter for recycling. When acontinuous ink jet printing technique is used the ink compositionpreferably also contains a conducting material such as an ionised saltto enhance and stabilise the charge applied to the ink drops duringejection from the printer head. Suitable salts for this purpose arealkali metal salts of mineral acids.

The heating in step iii) of the method according to the fourth aspect ofthe invention, to fix the dye to the polyamide textile material, may beperformed using any convenient heating method. Preferred heating methodsare hot air heating, microwave heating, electron beam heating, steamheating or a combination of steam and microwave heating. Preferably heatis applied in step iii) for a period of up to 60 minutes, this fixes thedye onto the polyamide textile material. When a steam (wet) heattreatment is used, the heating is preferably performed at 100-105° C.for from 5 to 40, more preferably from 10 to 35 minutes. If hot airheating is employed the heating is preferably performed at 140-160° C.for from 2 to 8 minutes.

After step iii) the textile material is preferably washed using a seriesof hot and cold washes in water and aqueous detergent solutions. Washingremoves any unfixed dye and other ingredients of the composition fromthe printed polyamide textile material.

A preferred washing method comprises the steps:

step (a) a cold wash in an aqueous alkaline medium, preferably at atemperature of from 5 to 30° C.;

step (b) a hot wash in water at a temperature of from 50 to 80, morepreferably 55 to 65° C.; and optionally

step (c) a cold wash in water containing a fabric softener, preferablyat a temperature of from 5 to 30° C.

We have found that this washing method minimises staining of the whiteundyed portions of the cloth and results in a textile with good handlingproperties. Good handling properties or “feel” of a material isparticularly desirable in delicate fabrics such as silk.

The cold wash in stage (a) is preferably performed in water whichcontains sufficient alkali to neutralise the acid used in thecomposition according to the first aspect of the present invention. Thedesired alkaline conditions may be achieved by adding a suitablealkaline material to water. Preferably the alkaline material is ammoniasolution.

An especially preferred stage (a) cold water wash comprises watercontaining from 0.4 to 0.6g/litre of a 35% aqueous ammonia solution. Wehave found that wash off solutions which contain less ammonia results inprints which exhibit staining of the un-dyed, portions of the fabric.However, if more ammonia is added the anionic dyes on the fabric surfaceare neutralised which results in undesirable loss of dye fixation andprints which exhibit a poor colour yield.

Preferably the hot wash in stage (b) contains a suitable soap and/orsurfactant to aid removal of unfixed dye from the textile. Preferredsoaps are anionic soaps. When a surfactant is used it may be ionic ornon ionic or a mixture of ionic and non-ionic surfactants. It isespecially preferred that the hot bath used in stage (c) contains from0.5 to 3, more preferably 0.75 to 2 and especially from 0.8 to 1.5g/litre of a non-ionic surfactant, for example Sunaptol™ P-Extra,available from ICI.

A preferred fabric softener used in stage (c) of the wash-off procedureis Edunine™CSA, which is commercially available from ICI Ltd. The coldwash in stage (c) preferably contains from 0.5 to 4, more preferablyfrom 1 to 3 g/litre of fabric softener.

According to a fifth aspect of the present invention there is provided apolyamide textile material coloured by means of the method according tothe fourth aspect of the present invention.

The invention is further illustrated by the following Examples in whichall parts and percentages are by weight unless otherwise stated.

EXAMPLE 1 Ink Formulations

Dye (1)

Dye (1) is commercially available as Cl Acid Yellow 23

Dye (2)

Dye (2) is commercially available as Cl Direct Blue 199

Dye (3)

Dye (3) is commercially available as Cl Acid Blue 90

Dye (4)

Dye (4) is commercially available as Cl Acid Red 52

Dye (5)

Dye (5) is commercially available as Cl Direct Black 168

Dye (6)

Dye (6) is commercially available as Cl Reactive Yellow 85.

Inks

Ink (1):

5 parts Dye (1);

5 parts 4-(2-hydroxyethyl)morpholine;

90 parts water

Ink (1) was prepared by mixing the above components with stirring. Theresulting mixture was then filtered through a 0.45 μm filter to give theink. Inks (2) to (6) shown in Table 1 were prepared using an analogousmethod to that described for Ink (1).

In Table 1 the following abbreviations are used:

HEM = 4-(2-hydroxyethyl)morpholine 2-P = 2-pyrrolidone GLY = glycerol

The column marked “Dye parts” refers to the number of parts by weight ofthe relevant dye. The numbers in the columns 3 to 6 refer to the numberof parts by weight of the relevant formulant shown.

Ink Jet Printing Each of the inks shown in Table 1 was loaded ink into aStork TCP-20-20 continuous ink jet printer head. The inks were thenejected from the head vertically downwards.

The jetting performance of each ink was assessed by measuring thedistance travelled by the ink droplets from the nozzle of the ink jethead before the droplets distorted or fragmented into smaller droplets.A stroboscope was used to view the individual ink droplets and measurethe jetting distance visually against a ruled scale. A suitableobservation apparatus is described in the proceedings of the IS&T NIP-12Conference on Digital Printing Technologies 1996, p.38.

In Table 1 the column marked “jetting distance” refers to the distancetravelled by an the ink droplets prior to droplet distortion orfragmentation.

TABLE 1 Jetting Dye Distance Ink Dye parts 2-P HEM GLY Water (mm) Ink(1) Dye (1) 5 0 5 0 90 14.28 Ink (2) Dye (2) 5 0 5 0 90 13.67 Ink (3)Dye (3) 5 0 5 0 90 13.01 Ink (4) Dye (4) 5 6 3 0 86 11.03 Ink (5) Dye(5) 5 6 3 0 86 11.39 Ink (6) Dye (6) 5 6 3 0 86 17.22 Ink (7) Dye (5) 53 6 86 11.33 Ink (8) Dye (5) 5 4.5 4.5 0 86 10.70 Ink (9) Dye (5) 5 3 33 86 10.69 Ink (10) Dye (4) 5 3 6 0 86 8.91 Ink (11) Dye (4) 5 4.5 4.5 086 9.66 Ink (12) Dye (4) 5 3 3 3 86 9.14 Comparative Dye (4) 5 0 0 5 906.11 (1) Comparative Dye (5) 5 0 0 5 90 3.60 (2) Comparative Dye (5) 5 50 0 90 7.61 (3)

The further the ink can be jetted without distorting or fragmentationthe better the jetting performance of the ink. A high jetting distanceis desirable because this reduces the scatter and thus minimisesblurring and feathering of the printed image

From Table 1 it is clear that the inks according to the first preferredembodiment of the fourth aspect of the present invention (Inks(1) to(12)) exhibit excellent jetting performance compared to Comparative inks(1) to (3).

The inks shown in Table 1 were assessed for dry-out properties byplacing 5 g of each ink into a 60 ml open topped sample bottle. Each inkwas then left at ambient temperature in the open jars for a period of 72hours. After this time the mass lost by each ink was calculated. Each ofthe inks was examined under an optical microscope for evidence of dyecrystallisation.

In Table 2 Inks (2), (4), (5) and (6) are the inks described in Table 1.Control (1), (2), (3) and (4) refer to control inks comprising 5 partsof Dye (4), (2), (6) and (5) respectively in 95 parts water.

TABLE 2 % weight loss Dye crystallisation Ink after 72 hours presentafter 72 hours Ink (4) 48.5 no Control (1) 70.2 yes Ink (2) 48.0 noControl (2) 64.1 yes Ink (6) 43.8 no Control (6) 64.1 yes Ink (5) 44.8no Control (5) 70.6 yes

The results in Table 2 clearly show that the inks according to the firstpreferred embodiment of the method according to the fourth aspect of thepresent invention exhibit excellent dry-out properties and are stable tostorage.

EXAMPLE 2: Pre-Treatment Composition (PTC-1): (Composition According tothe Second Aspect of the Invention)

Stage (a): Preparation

PTC-1 Comprised:

20 parts distearyl dimethylammonium chloride (cationic substance);

15 parts Solvitose WB (hydroxypropylated starch);

0.5 parts citric acid; and

64.5 parts water.

(Solvitose WB is commercially available from Avebe, Holland.)

PTC-1 was prepared by adding the distearyl dimethyammonium chloride,Solvitose WB and citric acid to water at a temperature of 40 to 50° C.The mixture was then stirred until all of the components were insolution.

Stage (b): Application

PTC-1 was applied to Habotai silk (commercially available from Whaleys(Bradford) Ltd) by padding using a Hall and Boyden padder operated atroller speed of 4 rpm and with a pressure of 1 bar applied between therollers.

The padded silk was then dried at 70° C. for approximately 2 to 3minutes using a Roaches TFO Series drier.

EXAMPLE 3

Further pre-treatment compositions (PTC-2,-3, 4 and -5)) shown in Table3 and the Comparative formulations shown in Table 4 were prepared usingan analogous method to that described in stage (a) of Example 1. Each ofthe compositions shown in Tables 3 and 4 was applied to Habotai Silk bypadding as described in stage (b) of Example 1.

In Tables 3 and 4 DSDMAC is distearyldimethylammonium chloride.

The pre-treated silk fabrics shown in Tables 3 and 4 were ink jetprinted with each of Inks (2), (5), (6) and (4) shown in Table 1 using aStork TCP-20-20 continuous ink jet printer (i.e. cyan, black, yellow andmagenta inks).

After printing each fabric sample was subjected to steam heating at 102°C. for 8 minutes. The fabrics were then washed using steps (a), (b), (c)and (d):

(a) a cold (ambient temperature) rinse in water containing 0.5 g/litreof 35% ammonia solution;

(b) a hot rinse at 60° C. in water containing 1 g/litre of Sunaptol PExtra (a surfactant available from ICI);

(c) a cold rinse in water at ambient temperature; and

(d) a cold rinse in water containing 2 g/litre Edunine CSA (a softener)available from ICI.

The colour yield of each print was assessed by reflectancespectrophotometry using the method of Derbyshire and Marshall (J.Society of Dyers and Colourists, volume 96 (1980) page 166) which isbased on the Kubelka-Munk equation (Z. Tech. Physik, volume 12 (1931)page 593) and termed the ‘Integ’ value:${Integ} = {\sum\limits_{400}^{700}\quad {I_{\lambda} \cdot F_{\lambda} \cdot \left( {{\overset{\_}{X}}_{\lambda} + {\overset{\_}{Y}}_{\lambda} + {\overset{\_}{Z}}_{\lambda}} \right)}}$

where$F_{\lambda} = {\frac{\left\lbrack {1 - \left( {R_{\lambda} - R_{o}} \right)} \right\rbrack^{2}}{2\left( {R_{\lambda} - R_{o}} \right)} - \frac{\left\lbrack {1 - \left( {R_{s} - R_{o}} \right)} \right\rbrack^{2}}{2\left( {R_{s} - R_{o}} \right)}}$

R_(λ) k reflectance of the print at wavelength λ

R₉ reflectance of the undyed substrate at the same wavelength

R_(o) constant

I_(λ) is the spectral energy of illuminant D65

x, y, z are the 10° standard observer data.

The degree of staining on the unprinted parts of the fabric was assessedvisually on a scale of 1 to 5, in which 5 equates to no staining and 1to significant staining of undyed fabric.

The colour yield (Integ) and staining results are shown in Table 5.

TABLE 3 Compositions According to the Second Aspect of the InventionComponent (Parts) Solvitose Citric Malonic Succinic Nicotinic SodiumComposition DSDMAC WB Acid Acid Acid Acid Alginate Water PTC-1 20 15 0.50.5 64.5 PTC-2 20 15 0.5 64.5 PTC-3 20 15 0.5 64.5 PTC-4 20 15 0.5 64.5PTC-5 20 15 0.5 64.5

TABLE 4 Comparative Pre-Treatment Compositions Component (Parts)Solvitose Citric Malonic Succinic Nicotinic Sodium Composition DSDMAC WBAcid Acid Acid Acid Alginate Water Comparative 1 0 15 0.5 84.5Comparative 2 20 15 0 65 Comparative 3 20 0 0.5 79.5 Comparative 4 0 150.5 84.5 Comparative 5 0 15 0.5 84.5 Comparative 6 0 15 0.5 84.5Comparative 7 0 15 0.5 84.5

TABLE 5 Integ Value Degree of Staining Textile sample Ink (Colour Yield)(1-5) PTC-1 Ink (6) 4.92 5 Ink (4) 13.56 5 Ink (2) 10.05 5 Ink (5) 20.975 Comparative 1 Ink (6) 5.05 5 (No DSDMAC) Ink (4) 12.06 3 Ink (2) 2.435 Ink (5) 8.93 5 Comparative 2 Ink (6) 4.42 3 (No acid) Ink (4) 14.252-3 Ink (2) 6.74 4 Ink (5) 10.53 5 Comparative 3 Ink (6) 2.07 5 (Nohydroxy Ink (4) 5.85 5 propylated starch) Ink (2) 4.34 5 Ink (5) 8.67 5PTC-2 Ink (6) 2.9 5 Ink (4) 10.7 3 Ink (2) 8.56 5 Ink (5) 12.86 5Comparative 4 Ink (6) 3.54 5 No DSDMAC Ink (4) 8.8 3 Ink (2) 2.99 5 Ink(5) 12.86 5 PTC-3 Ink (6) 3.1 5 Ink (4) 8.22 4 Ink (2) 9.67 5 Ink (5)15.87 5 Comparative 5 Ink (6) 3.0 5 No DSDMAC Ink (4) 7.35 4 Ink (2)2.21 5 Ink (5) 10.92 5 PTC 4 Ink (6) 3.03 5 Ink (4) 7.02 4 Ink (2) 9.495 Ink (5) 13.77 5 Comparative 6 Ink (6) 4.02 5 (No DSDMAC) Ink (4) 1.942 Ink (2) 1.71 2 Ink (5) 10.23 5 PTC 5 Ink (6) 4.17 5 Ink (4) 7.63 4 Ink(2) 9.83 5 Ink (5) (4.4) 5 Comparative 7 Ink (6) 4.13 5 (No DSDMAC) Ink(4) 1.82 4 Ink (2) 3.95 5 Ink (5) 11.67 5

The results in Table 5 clearly show that only those fabrics which havebeen treated with a pre-treatment composition according to the presentinvention exhibit a high colour yield for all of the inks (cyan,magenta, yellow and black) in combination with little or no staining ofunprinted fabric.

For example, a comparison of PTC-1 with Comparative 3 shows that whenthe composition containing the Solvitose WB (hydroxypropylated starch)is applied to the silk the resulting print has a high colour yield forall inks compared to the composition without the Solvitose WB.

What is claimed is:
 1. An aqueous composition having a pH from 2 to 7comprising a) a cationic substance of formula 1

wherein R¹, R² and R³ are each, independently, selected from H,optionally substituted C₁₋₂₀-alkyl and optionally substitutedC₂₋₂₀-alkenyl; R⁴ is optionally substituted C₁₋₂₀-alkyl or optionallysubstituted C₂₋₂₀-alkenyl; and X is an anion; b) an inorganic or organicacid; and c) an alkyl or hydroxyalkyl substituted starch.
 2. An aqueouscomposition as claimed in claim 1 having a pH from 3.5 to 5.5.
 3. Anaqueous composition as claimed in either claim 1 or claim 2 wherein thecationic substanoe is a distearyldimetnylammonium salt.
 4. An aqueouscomposition as claimed in claim 1 wherein the acid is selected fromnicotinic, citric, tartaric and malonic acids.
 5. An aqueous compositionas claimed in claim 1 comprising: from 0.5 to 99.5 parts of component(a); from 0.1 to 60 parts of component (b); and from 0.1 to 99.5 partsof component (c); wherein all parts are by weight and the sum of theparts of component (a)+(b)+(c)=100.
 6. An aqueous compostion as claimedin claim 1 wherein component (c) is a C₁₋₈-alkyl substituted starch or aC₂₋₄-hydroxyalkyl substituted starch.
 7. An aqueous compositon asclaimed in claim 1 wherein component (c) is hydroxypropyl substitutedtapioca starch.
 8. A polyamide textile material treated with acomposition as claimed in claim
 1. 9. A method for the coloration of apolyamide textile material comprising the steps: i) treating thepolyamide textile material with a composition as claimed in claim 1; ii)applying by means of an ink jet printer an ink composition comprising aliquid medium and water-soluble anionic dye, or a salt thereof, to theproduct of step i); and iii) heating the product of step ii) at atemperature of from 50° C. to 250° C.
 10. A method as claimed in claim 9wherein the ink comprises: (a) from 0.05 to 30 parts of a water-solubleanionic dye; (b) from 0.01 to 50 parts of a compound of the Formula (3):

wherein: R⁸ and each R¹⁰ independenty, is H or optionally substitutedalkyl; and t has a value of 1 to 4; (c) from 0 to 50 parts of2-pyrrolidone; (d) from 0 to 30 parts of one or more compounds selectedfrom glycerol, polyethylene glycol 200, polyethylene glycol 400 or apolyethoxylated 2-naphthol; and (e) from 40 to 99 parts water; whereinall parts are by weight and the sum of the parts(a)+(b)+(c)+(d)+(e)=100.
 11. A method as claimed in claim 10 wherein R¹⁰is H and R⁸ is H or C₂₋₄-hydroxyalkyl.
 12. A method as claimed in claim9 wherein the ink is selected from one or more inks comprising: (a) ablack ink comprising a liquid medium and a dye selected from Cl DirectBlack 195, Cl Direct Black 168 and Cl Direct Black 19; (b) a cyan inkcomprising a liquid medium and a dye selected from Cl Acid Blue 9, ClAcid Blue 158, Cl Acid Blue 90 and Directed Blue 199; (c) a magenta inkcomprising a liquid medium and a dye selected from Cl Acid Red 52, ClAcid Red 249, Cl Direct Violet 107, Cl Direct Violet 106 and Cl ReactiveRed 31; and (d) a yellow ink comprising a liquid medium and a dyeselected from Cl Direct Yellow 86, Direct Yellow 132, Direct Yellow 173,Cl Reactive Yellow 85 and Cl Acid Yellow
 23. 13. A method as claimed inclaim 9 wherein the product of step iii) is subjected to a washingmethod comprising the steps: step (a) a cold wash in an aqueous alkalinemedium; step (b) a hot wash in water at a temperature of from 50 to 80°C.; and optionally step (c) a cold wash in water containing a fabricsoftener.
 14. A polyamide textile material coloured by means of theprocess as claimed in claim 9.